By popular demand, here is release -v20 of the CFS scheduler. It is a full backport of the latest & greatest v2.6.23-rc3 CFS code to v2.6.22.5, v2.6.21.7 and v2.6.20.16. The patches can be downloaded from the usual place:

Changes since -v19: there have been lots of small regression fixes,speedups, debug enhancements and tidy-ups - many of which can beuser-visible.

See the detailed shortlog below - there are nearly 100 changes - they do add up to a significant total linecount change. There was no crash bug or hang bug found in the CFS code since v19 was released. (in fact the last crash/hang bug in CFS was found and fixed in v7, more than 3 months ago, and even that crash only happened in an uncommon sw-suspend setup, not during normal use. So CFS has turned out to be a pretty robust codebase.)

Nevertheless, if you had any problems (performance or behavioral) withv19 it's worth checking v20 out - and if v19 worked great for you it'sworth checking out that v20 still works great =B-)

Also, the backported CFS scheduler enables people to test suspected scheduler regressions on older codebases too, to filter out the effects of other changes.

v20 has been build and boot tested on both 32-bit and 64-bit x86, ontop of all 3 backport kernel bases. As usual, any sort of feedback, bugreport, fix and suggestion is more than welcome!